Eight gravity cores (GC) were retrieved from the deep mud volcanoes Sagres, Bonjardim, Soloviev and Porto in the Gulf of Cadiz. Cores with 137 to 317 cm long were sliced in intervals of 15 to 20 cm thickness, and 46 samples were analyzed for grain size distribution, loss on ignition, Al, Fe, Ca, Mg, Mn, Sr, Ba and the rare earth elements (REE) La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb and Lu. REE profile normalized to Post-Archean Australian Average Shale (PAAS) was dominated by a mid-REE bulge with a pronounced Eu enhancement. Sediment reducing conditions resulting from the anaerobic oxidation of methane probably contributed to the positive-Eu anomaly (1.18–2.19, PAAS normalization). Most likely, reactions near the sulfate-methane transition zone such as the precipitation of barium sulfate found at layers around 50-cm depth explain the enhancement of Eu/Eu* ratios. The Ce anomalies (0.93–1.09) were almost absent.

从加的斯湾的深层泥火山萨格里什，邦加尔丁，索洛维耶夫和波尔图取回了八个重力岩心。将长度为137至317 cm的铁心切成15至20 cm的厚度，并分析46个样品的晶粒尺寸分布，灼烧损失，Al，Fe，Ca，Mg，Mn，Sr，Ba和稀土元素（REE）La，Ce，Pr，Nd，Sm，Eu，Gd，Dy，Ho，Er，Tm，Yb和Lu。归一化为后Archean澳大利亚平均页岩气（PAAS）的REE剖面以中等的REE隆起为主导，其Eu增强明显。甲烷厌氧氧化导致的沉积物减少条件可能导致正Eu异常（1.18–2.19，PAAS归一化）。最有可能的，硫酸盐-甲烷过渡带附近的反应，例如在50-cm深度的层上发现硫酸钡的沉淀，可以解释Eu / Eu *比值的提高。Ce异常（0.93-1.09）几乎不存在。